Radek, he is better than Scopica. Not opinionally statistically. If Radek faced someone he is a 9/5 and Scopica is a 8/6, Scopica may have more damage but power is everything these days, and if They are hit by SOA Radek is a 7/5 which is still good for level 3 but Scopica goes to a 8/4 which is also good but if Scopica gets hit by SOA she has less chance to make a difference. Plus Radek is more common than Scopica, so I would choose Radek. For a tip here is top 3* cards... 1-Radek, 2-Jalil, 3-Scopica
Personally, I'd say Radek is the best Jungo 3*, followed by Scopica, then Jalil, and last, Odile. All these cards a viable options at 3* for Jungo. As excallibur said, power matters more than damage. Odile has lower base power than the other 3, thus she's on the lower end. Radek is like a 9 power and is base 7 which is still very good. Scopica has a high 8 power and is 8/4 even when hit with SOA or SOB. Jalil is a virtual 7/7 at 3* so again, extremely viable option.
I have played with all but Odile, all are very similar, I have found radek to lack a lot of punch when opponent has a reducer.
I am surprised by the amount of combats I lose winning 2 rounds with a clan whose bonus is +2 life.
Scopica is much more reliable when you need someone to SEND (its the best card to counter uranus), radek is better to receive. If you find yourself very often badly placed when having to send someone you would rather use scopica.
Radek is wonderful when you want to overkill power 7/6 cards without bonus/SOA, but there aren't many of them.
One more thing, if you have Slith, Sheitane or any freak to score on first round, Scopica is a major threat for round 2, you can bluff with it since scoring with it equaks a 2 hit ko probably.
That means that even if you wasted too much pillz on first round Scopica is giving you around 2/3 chances of winning, if you wasted so much many pillz (like you at least have 1/3 thx to scopica now.